Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
Processing...

Test String

Code Generator

Language

Generated Code

const regex = /CIgcCursor.*<.*>\s*(\w*)[^}]*?(?:while|for)\s*\(.*?\n.*?(\{(?>[^{}]|(?-1))*\})/g; // Alternative syntax using RegExp constructor // const regex = new RegExp('CIgcCursor.*<.*>\\s*(\\w*)[^}]*?(?:while|for)\\s*\\(.*?\\n.*?(\\{(?>[^{}]|(?-1))*\\})', 'g') const str = `Return_t rgRoadNameChanges(Maneuver_o *pManeuverObj, rgManeuver_t *pManeuver, bool& bIsChanged) { Return_t Result; Sint_t iIndex; utSegment_t Seg; utSegmentInfo_t SegInfo; Uint_t nDist = 0; DBID_t prevNavFeatureID; DBID_t currDBID; CIgcCursor_Sdal<DBNavFeatureAndAttrs_t> cursorFeature(true); bIsChanged = false; DBID_SET_NULL(prevNavFeatureID); iIndex = pManeuver->RouteIndex; while (nDist < 800) { if ((Result = utRouteGetSegment(pManeuverObj->hRoute, &Seg, iIndex)) == SDAL_FAILURE) return NT_SUCCESS; if ((Result = utSegmentGetInfo(&Seg, &SegInfo, NULL)) == SDAL_FAILURE) return NT_TRACE(Result, NT_ERR_STR("rgRoadNameChanges: utSegmentGetInfo failed!")); if ((Result = utSegmentGetDBID(&Seg, &currDBID, NULL)) == SDAL_FAILURE) return NT_TRACE(Result, NT_ERR_STR("rgRoadNameChanges: utSegmentGetDBID failed!")); Result = iDbGetSegNavFeatures(&currDBID, 0, cursorFeature); if (Result > 0) { // Just comparing the first nav features for now. I don't know if we // need to check all against the other list in case the order of the // nav features changes. I'm assuming they'll stay the same order. if (!(++cursorFeature).NoMoreRecords()) { if (!DBID_IS_NULL(prevNavFeatureID) && (iGuCompareDBIDsEqual(&prevNavFeatureID, &cursorFeature->navFeature.navFeatureID, GU_COMPARE_FULL_IDS) != 0)) { bIsChanged = true; break; } utMemcpy(&prevNavFeatureID, &cursorFeature->navFeature.navFeatureID, sizeof(DBID_t)); } } nDist += SegInfo.length; iIndex++; } }`; // Reset `lastIndex` if this regex is defined globally // regex.lastIndex = 0; let m; while ((m = regex.exec(str)) !== null) { // This is necessary to avoid infinite loops with zero-width matches if (m.index === regex.lastIndex) { regex.lastIndex++; } // The result can be accessed through the `m`-variable. m.forEach((match, groupIndex) => { console.log(`Found match, group ${groupIndex}: ${match}`); }); }

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions